Numerical Simulation Research on Wellbore Stability of Ultra-Deep and High-Pressure Gas Wells

The block S Formation reservoir in the southern edge thrust belt's Huomatu anticline is distinguished by ultra-deep, high-temperature, and high-pressure features. Perforation completion is the standard procedure for super deep wells under current completion technologies. By optimizing perforation parameters, perforation completion not only maximizes production pressure difference but also lowers reservoir sand output. To clarify the progressiveness of perforated completion in ultra deep well completion, this paper uses the M well at the south edge as an example. Using an indoor rock mechanics parameter test, more accurate rock mechanics parameters and crustal stress field size are obtained based on the target well logging interpretation, and open hole completion and perforated completion wellbore stability are evaluated using geological modeling and finite element simulation. According to the simulation results, perforated completion has a bigger allowed production pressure differential under the same formation pressure conditions. When the formation pressure is 146MPa, the production pressure differential between perforated and open hole completions increases by 85%. When the formation pressure falls below 70 MPa, open hole completion cannot be produced regularly, and the safe production pressure difference of perforated completion remains approximately 26 MPa.